Rules versus discretion - A disinflation case

This paper compares a strict inflation target regime to a conservative central bank regime to determine the monetary regime appropriate for a disinflation process. The analysis shows that in a two-period model, in which policymakers face given first-period inflationary expectations, a strict inflation target could be preferred to the appointment of a conservative central banker who has discretion. The result differs from that of Rogoff (1985), who assumed rational expectations and concluded that a conservative central banker is always preferable. The disadvantage of the conservative central banker derives from his tendency to accelerate disinflation relative to rate that maximizes social welfare.JEL Classification: E52, E58The authors are grateful to Alex Cukierman, Nissan Liviatan, Allan Drazen, Amit Friedman and Yoav Friedmann for their useful suggestions. We also thank the anonymous referees for helpful comments. Earlier versions of this paper were presented at the Tel Aviv University macroeconomic workshop, at the Research Department seminar, Bank of Israel, and at the Bank of Israels conference on Macroeconomic Policy, October 2002.     

恶劣环境对船舶焊接的影响

在船舶建造过程中焊接工作量约占全部的30%~40%，焊接是保证质量的重中之重。焊接质量出问题，就可能造成严重的后果。我厂沿江堤而建，空气中湿度大，工作条件差。密集性气孔很严重。所以，在这种情况下，对我厂焊接质量控制提出更高的要求。     

Do constraints created by economic growth targets benefit sustainable development? Evidence from China

An economic growth target is a declaration by policy authorities of commitment to that target and the corresponding allocation of resources. The constraints created by economic growth target are an important economic management method in China, which has helped China's economy to achieve remarkable achievements. However, it has also brought about serious environmental problems, threatening China's sustainable development. Using the data about economic growth targets in the work reports of 30 Chinese provincial governments from 2006 to 2017, this paper constructs several spatial measurement methods, such as the spatial Durbin model, to examine the constraints created by economic growth target's impacts on air pollution. The main conclusions are as follows. First, a significant “U-shaped” relationship exists between the constraints created by economic growth targets and air pollution. Second, the spatial Durbin model analysis revealed that PM_2.5 across China's provinces display significant positive spatial spillover effects and spatial agglomeration characteristics. Third, the direct, indirect, and total effects of constraints created by economic growth targets on air pollution are all statistically significant and depict a “U shape.” Finally, the constraints created by economic growth targets have an apparent threshold effect on air pollution, and the inhibiting effects increase with human capital and industrial restructuring. However, with the increase in foreign direct investments, constraints created by economic growth targets may increase air pollution. The conclusions of this paper are of great significance for improving the management of local government economic growth targets and sustainable development.     

利用改进特征金字塔模型的SAR图像多目标船舶检测

深度学习模型中的特征金字塔网络（Feature Pyramid Network，FPN）常被用作合成孔径雷达（Synthetic Aperture Radar，SAR）图像中多目标船舶的检测。针对复杂场景下多目标船舶检测问题，提出了一种基于改进锚点框的FPN模型。首先将特征金字塔模型嵌入传统的RPN（Region Proposal Network）并映射成新的特征空间用于目标检测，然后利用基于形状相似度距离（Shape Similar Distance,SSD）度量的Kmeans聚类算法优化FPN的初始锚点框，并使用SAR船舶数据集测试。实验结果表明，所提算法目标检测精确率达到98.62%，在复杂场景下与YOLO、Faster RCNN、FPN based on VGG/ResNet等模型进行对比，模型准确率提高，整体性能更好。     

船舶过闸辅助调度系统

针对现有内河航运船舶过闸管理存在工作效率较低,安全性较差,服务不到位等问题,提出基于RFID和GSM的船舶过闸辅助调度系统。以船舶预调度和自动过闸方式对带有芯片的船舶进行自动识别,读取数据;对遇到相关异常情况及时进行处理;根据船舶相关属性信息安排过闸调度,实现自动收费。并对该系统的基本工作原理、整体结构和实现方案等问题进行论述。     

以船舶工业为特色的数字资源库建设探讨

阐述了我校图书馆在学校办学过程中形成的以船舶工业为特色的独特的馆藏资源,通过对学校在教学科研所获得的成果进行收集、整理,探讨在此基础上建立数字资源库及必须注意的问题。     

浅析外贸公司在代理大型船舶出口业务中的风险防范

近年来我国的民营船厂发展迅速,但由于民营船厂缺乏足够的资金和信用能力,大多采用由外贸公司承担对外开立预付款银行保函和提供信用担保的出口代理角色.本文分析了这种模式下外贸公司承担的风险,并提出了应采取的风险防范措施.     

基于显著区域提取的红外图像舰船目标检测

针对复杂海面背景下红外图像舰船目标由于灰度不均匀、海杂波干扰大等因素造成的自动检测虚警率高、准确率低的问题,提出了一种显著区域提取和目标精确分割相结合的红外舰船目标检测方法。首先,利用基于图论的视觉显著性(Graph-based Visual Saliency ,GBVS)模型计算待检测图像的显著图,使得目标区域信息增强;其次,结合舰船目标先验信息（长短轴、面积等）,利用多级阈值划分算法提取关注的显著区域,并确定原图中候选目标区域;最后,利用空间约束模糊C均值(Fuzzy C-Means,FCM)算法对候选区域进行分割,结合目标先验知识对分割区域筛选并输出目标位置。所提方法在公开数据集IRShips上与相关方法进行比较,结果表明,相比直接进行全图目标搜索的方法,所提方法不仅准确率高、执行速度快,且检测目标的位置更加精确。     

基于MLE算法的海上角度交会测量方法及其精度分析

针对我国现有测量船单站REA测量体制精度相对较低的问题,提出了基于光电经纬仪 的海上角度交会测量方法。介绍了角度交会测量原理和设备布站原则,构建了AE-AE异面交 会测量系统,设计了基于MLE（Maximum Likelihood Estimation）算法的海上角度交会测量 算 法和船摇修正方法,仿真分析了船体姿态测量误差、设备测角误差以及站址定位误差等的影 响。仿真结果表明,站址测量误差是海上角度交会测量的最主要误差源,船体姿态测量误差 和设备测角误差对海上角度交会测量精度有一定的影响,当船体水平姿态测量误差优于20″ 、航向测量误差优于30″、设备测角误差优于20″、站址测量误差优于1 m时,海上角 度交会测量精度可达1 m。该法解决了动态条件下的飞行目标高精度测量技术难题,为 后续工程设计奠定了基础。     

从耕地保护目标论耕地保护机制的功能

在明确耕地保护目标的基础上,通过耕地保护目标在耕地保护机制中3个层次的体现,提出了耕地保护机制应具备的功能。